What it is
CVE-2026-8452 is an unauthenticated vulnerability affecting NetScaler ADC, Gateway. Memory overflow vulnerability NetScaler ADC and NetScaler Gateway leading to unpredictable or erroneous behavior and Denial of...
Vulnerability report
Active exploitation observed
Confirmed confidence
Not in CISA KEV
CVE-2026-8452
ADC Denial of Service
NetScaler / ADC · affected before 72.61
- Severity
- CVSS 8.8 · High
- Confidence
- Confirmed
- Exploit status
- Observed in sensors
- EPSS
- 0.5%
- First observed
- 17 Aug 2026
- Last observed
- 17 Aug 2026
Decision summary
What security teams need to know first
Direct answers before the deeper technical record.
Is it exploited?
Yes. KEV Intelligence sensors observed exploitation attempts with confirmed confidence.
Who is affected?
NetScaler / ADC affected before 72.61.
What should we do?
Patch immediately, validate internet-facing exposure, and monitor for matching requests.
Overview
ADC Denial of Service
Memory overflow vulnerability NetScaler ADC and NetScaler Gateway leading to unpredictable or erroneous behavior and Denial of Service if the appliance is configured as a Gateway (SSL VPN, ICA Proxy, CVPN, RDP Proxy) or AAA virtual server
Vendor
Product
Affected
Status
NetScaler
ADC
Before 72.61
Affected
NetScaler
ADC
Before 63.18
Affected
NetScaler
ADC
Before 72.61
Affected
NetScaler
ADC
Before 37.272
Affected
NetScaler
Gateway
Before 72.61
Affected
NetScaler
Gateway
Before 63.18
Affected
- Published
- 30 Jun 2026
- Exploited Since
- 17 Aug 2026
- Attack vector
- Remote
- Complexity
- Low
- Privileges
- None
- User interaction
- None
CVE References
- support.citrix.com/support-home/kbsearch/article support.citrix.com · CVE Record https://support.citrix.com/support-home/kbsearch/article?articleNumbe...
Exploitation evidence
Why KEV Intelligence marks this CVE as exploited
Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.
Exploited in the wild
KEV Intelligence
Independent exploitation attestation added to the KEV Intelligence record.
Active exploitation observed
KEV Intelligence sensor
First-party sensor telemetry confirms matching exploitation attempts.
Proof of concept available
Public scanner or PoC coverage increases practical exploitability.
Known exploited vulnerability sources
Per-source evidence links for KEV attestations are available through the KEV Intelligence Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| KEV Intelligence First | 2026-08-17 08:04 UTC |
Operational indicators for this CVE are listed under Detection.
Sensor telemetry
First-party evidence of exploitation activity
Aggregate observations show the scale, recency, and distribution of activity without overstating sparse data.
7
Attempts observed
5
Unique attacker IPs
4
Attacker countries
JP · SG · TR · US
1
Sensors observed
Exploitation attempts over the last 7 days
Daily events observed by KEV Intelligence sensors
Updated 17 Aug 2026
11 Aug
12 Aug
13 Aug
14 Aug
15 Aug
16 Aug
17 Aug
First observed 17 Aug 2026 · Last observed 17 Aug 2026
Pro adds sensor region and window summaries. Enterprise adds raw IPs, paths, User-Agents, and payloads.
Detection
Operational artifacts and observed signals
Make the evidence actionable in scanner, SOC, and edge-control workflows.
Observed signals
- Request targets
- 6
- User-Agents
- 6
Raw values available in Pro and Enterprise.
Scanner coverage
No scanner integrations recorded yet.
Virtual patch status
No KEV Intelligence virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.
Learn about virtual patches →Attacker IP Indicators
Attacker IP indicators observed · available in Pro and Enterprise.
Sensor-derived attacker IP indicators are available to Pro and Enterprise accounts under Detection and through the Pro API.
Learn about Pro API accessRisk and context
Severity, weaknesses, and research context
CVSS v4.0
8.8
High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:H/SC:L/SI:L/SA:L
EPSS
0.5%
Recent mention · Watchtower Labs
You’re Back In The Room (Citrix NetScaler Pre-Auth RCE CVE-2026-8452(?))
Suddenly, you’re in a room. You look around - oh, you’re surrounded by other new starters at your new job. Yes, it’s Monday, and you’re being onboarded.You know the drill - it’s the typical enterprise “please don’t be
Read full advisoryAll CVSS Scores
CVSS v4.0
8.8
High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:H/SC:L/SI:L/SA:L
CVSS v3.1
9.8
Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Potential Proof of Concepts
These PoCs are unverified and could contain malware. Use at your own risk.
watchTowr-vs-Citrix-Netscaler-PreAuth-RCE
public · Created 2026-08-14 19:42:00 UTC
Timeline
From disclosure to observed exploitation
-
Observed by KEV Intelligence sensors
Evidence-backed exploitation signal
-
Indicators of compromise added (5)
Indicators of compromise recorded
-
Public PoC available
Public proof-of-concept code published
-
CVE published
Vulnerability disclosed publicly
-
CVE ID reserved
Identifier reserved by the CNA
Pro API
Automate this intelligence
Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
- Evidence confidence and provenance
- First-party sensor telemetry
- PoC and scanner references
- Affected versions and enrichment
- Automation-ready JSON delivery
GET /api/v2/pro/kevs/CVE-2026-8452
Free JSON includes basic KEV fields{
"cve_id": "CVE-2026-8452",
"confidence": "Confirmed",
"cvss_score": 8.8,
"cvss_estimated": false,
"epss_score": 0.00487,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": true
},
"sensor_telemetry": { "attempts": 7, "sensors": 1 }
}Early warning alerts
Get alerts on high-impact exploitation
Receive curator-selected alerts when exploitation activity warrants attention. Each alert includes the evidence and context needed to decide what requires attention now.